Weed control in lampascione e Muscari comosum (L.) Mill

Weed management studies in lampascione e Muscari comosum (L.) Mill e a bulb crop, were carried out in the Apulia Region (southern Italy) in 2007e2008 and 2008e2009, using various pre- and postemergence herbicides. Herbicide treatments were compared with hand-weeded and unweeded controls. Weed control and crop injury index, yield, morphology and dry matter content of bulbs were recorded. The most dominant weed species were Veronica hederifolia L., Lamium purpureum L., and Stellaria media (L.) Vill. Manual weeding gave the highest yield (11.3 t/ha, on average), that was 31% higher compared to the unweeded control. During winter and until four months after planting, both pre-emergence herbicides were effective in keeping soil free from weeds, without negative effects on the sprouting or growth of lampascione bulbs. Among the tested post-emergence active ingredients, Oxyfluorfen, Oxadiazon, and Ioxynil- Pendimethalin and Oxyfluorfen þ Pendimethalin mixtures showed a low selectivity toward the crop. Despite a good weed control with a low level of crop injury, Ionyxil produced also negative effects on bulb dry matter. Pendimethalin and Chloridazon were variable in their effect and they did not provide clear results either in terms of phyto-toxicity or weed control, therefore they should be further investigated. Flazasulfuron always resulted in very low crop injury (14%, on average) and adequate weed control (56%, on average), while maintaining a 14% higher mean yield compared to the unweeded control and similar to the weed-free control. Since the lampascione crop has a long cycle from winter to early summer, we suggest that a combination of a pre-emergence herbicide (Chlorthal-dimethyl or Chlorpropham) in winter, followed by a post-emergence Flazasulfuron application at 100 g a.i./ha in early spring, should allow the best weed control without any negative effects on bulb yield.